---
id: daff
version: "1.4.2"
license: MIT
license_treatment: permissive
maintenance: active
---

# daff — Diff and patch tables

License: permissive · Maintenance: active · Popularity: top 1,000 on PyPI

## Install

pip install daff
uv add daff
poetry add daff

## Description

[![NPM version](https://badge.fury.io/js/daff.svg)](http://badge.fury.io/js/daff)
[![PyPI version](https://badge.fury.io/py/daff.svg)](http://badge.fury.io/py/daff)
[![PHP version](https://badge.fury.io/ph/paulfitz%2Fdaff-php.svg)](http://badge.fury.io/ph/paulfitz%2Fdaff-php)
[![Gem Version](https://badge.fury.io/rb/daff.svg)](http://badge.fury.io/rb/daff)

daff: data diff
===============

This is a library for comparing tables, producing a summary of their
differences, and using such a summary as a patch file.  It is
optimized for comparing tables that share a common origin, in other
words multiple versions of the "same" table.

For a live demo, see:
> https://paulfitz.github.io/daff/

Install the library for your favorite language:
````sh
npm install daff -g  # node/javascript
pip install daff     # python
gem install daff     # ruby
composer require paulfitz/daff-php  # php
install.packages('daff') # R wrapper by Edwin de Jonge
````

Use on the web from a CDN:
```
<script src="https://cdn.jsdelivr.net/npm/daff@latest/lib/daff.min.js"></script>
```

Other translations are available here:
> https://github.com/paulfitz/daff/releases/tag/v1.3.16

Or use the library to view csv...

## AI interpretation — verify before relying

daff compares two tables (CSV, JSON, SQLite, etc.), produces a structured diff showing row and column changes, and can apply those diffs as patches to transform one table into another.

Verdict: daff is a mature, actively maintained library for intelligent table diffing and patching across multiple formats. Zero security vulnerabilities, permissive MIT license, and no dependencies make it a low-friction choice for projects needing structured data comparison—though the Alpha classifier suggests API stability may still evolve.

[View on SkillFed](https://skillfed.io/packages/daff) · [View on PyPI](https://pypi.org/project/daff/)